research issues

• extraneous variable

  = any variable, other than the independent variable that may affect the dependent variable if its not controlled.
• confounding variables

  = a kind of extraneous variable but it varies systematically with the independent variable. Therefore we can't tell if any change in the dependent variable is due to the confounding variable or the independent variables.
• Demand characteristics

  = any cue from the researcher or from the research situation that may be interpreted by participants as revealing the purpose of an investigation. This may lead to a participant changing their behaviour within the research situation.

  • participants try to guess the aims of the experiment and behave in a way they think that they should.
• Investigator effects

  =any effect of the investigator's behaviour on the research outcome. This may include the design of the study, selection of participants, interaction with participants during the research process. eg: leading questions.
• Randomisation

  = the use of chance methods to control for the effects of bias when designing materials and deciding the order of experimental conditions.
• Standardisation

  = using exactly the same formalised procedures and instructions for all participants in a research study.